"Romania: Brigada Antiteroristă, (counter-terrorist brigade)"
BAT(Brigada Antitero/Antiteroristă) is the force of the internal intelligence agency, somehow similar to FBI's HRT. They aren't a police unit and they don't do police missions, they only do anti-terror missions and they're the ones designated to do it by the Constitution.
The police units are SIAS, DIAS, SPIR and an unnamed nuclear warfare unit. Either DIAS or SPIR has changed the name to SAS(Special Actions Service, Serviciul de Acțiuni Speciale, it has nothing to do with the British SAS, it's just a coincidence). There are also the Gendarmery units which may be considered police units because the gendarmes often do the jobs of policemen. The one to note here is BSIJ(Brigada Specială de Intervenție a Jandarmeriei, Gendarmery's Special Intervention Brigade)
The elite police unit of Romania is GSPI Acvila, which is formed from personnel from the other police units, somehow similar to GSG9 in that it is a pretty secretive unit that does a lot of hi-speed shit. It was disbanded until recently, when it was announced that they are being recreated. They're SWAT on steroids.
So, Ryan, Brigada Antitero is not a police unit at all.
The counter-terrorism units are BAT, BSIJ, Brigada 1 anti-teroristă, SIAT.http://romanianspecialforces.com/ <check this shit, pretty old site with some outdated info but it's a gold mine.

EDIT: There's also army's DIR, which is supposedly a tier 1 unit loosely based on the SAS that is allowed to operate domestically. BAT is still the number 1 CT unit from Romania.